Allochthonous granitic bodies in the northern marginal area of the Kanto Mountains

Geological and petrological studies were carried out on the granitic rocks in the Shimonita, Kanezawa and Yorii-Ogawa areas, northern margin of the Kanto Mountains. 1) The Late Cretaceous Namee granite intruding Jurassic Nanjai Formation is distributed to the north of the Okitano-Iwayama Line, correlative to the Median Tectonic Line, in the Shimonita area. It has been mylonitized with overprinted cataclasis. Based on the ore mineral composition and magnetic susceptibility, it shows ilmenite-series characteristics suggesting that it belongs to the Ryoke granite. 2) The Permian quartzdiorites in the above areas, have almost the same mineralogical and chemical composition and belong to the I-type. 3) The Early Cretaceous granitic rocks, the Yotsumatayama quartzdiorite and tonalites of the Yamagata body are characterized by presence of gneissosity, varying in modal content of hornblende andor biotite, and moderate Mg content of hornblende. They belong to the ilmenite-series and I-type granitic rock. -from English summary